whalesong

The peculiar clicking and whooshing sounds made by a PEPmodem such as the TelebitTrailblazer as it tries to
synchronise with another PEP modem for their special
high-speed mode. This sound isn't anything like the normal
two-tone handshake between conventional modems and is
instantly recognizable to anyone who has heard it more than
once. It sounds, in fact, very much like whale songs. This
noise is also called "the moose call" or "moose tones".